And so it begins... - PeachParts Mercedes-Benz Forum

dapperappy · #1 12-26-2007, 12:17 AM

Geez, was hoping i'd get a little more of a honeymoon period with this car..feel like i've hardly even been kissed...
Here's the deal, have driven it like 600 miles since i brought it home, no problems, runs fantastic, starts no problem. Had it out all day last saturday running all over town for last minute shopping with no problems all day stop and go. Coming home on the highway (75mph) i had a sudden loss of power, let off the gas and then stepped back on it hesitated then took off again like nothing was wrong, went about a half mile and same thing happened again.....this happened about 4 more times and thank god i was almost home, turned onto my street and it dies. Sat for a minute using language that makes me blush now and tried to start and it started right up and i got the short distance home with no other problems. No idiot lights came on during this whole episode except for when it totally died then the whole frigging cluster lit up with ever light. I haven't driven the car since....afraid of being stranded on the side of the road, not my idea of fun! I have researched this forum til i'm almost blind and have come up with it's either a fuel starvation problem or a MAF problem. Does this sound in the ballpark of a good guess? I'm going to take it to the independent guy this week and see what he says...just like to know what i may be hearing from him. I'm also wondering what a rough estimate is on having the fuel lines replaced, is it an expensive job?

I still love the car, i knew ahead of time i'd be running into this sort of thing.

Skid Row Joe · #2 12-26-2007, 12:47 AM

Did you study the service records on the car, since buying it?

Sounds like the fuel filters.

bgkast · #3 12-26-2007, 12:54 AM

How much fuel does the gauge show, and how long since the last fill up? It sounds like you are sucking air, it may be an empty tank or like you said, crusty lines.

Edit: I typed this thinking you had a older car. Maybe it will help somebody else so I will just leave it.

You can replace all of the rubber lines for about $10 and a hour or two of time. Just wait until the tank is nearly empty, then crawl under the rear and remove the two rubber lines that run between the tank and the metal lines that run the length of the car. Drain the excess fuel into a pan (careful, it eats asphalt) and swap out the rubber lines with similar lengths of 5/16 (I think) fuel injection hose. Then go up front and swap out the two bits of rubber line on each side of the pre-filter with the same type of hose.

Skid Row Joe · #4 12-26-2007, 01:05 AM

When I bought my then new to me '83 300SD, I ran it to almost empty, jacked-up the right rear, removed the fuel tank filter, and replaced it with a new one. Lines on the older Benzes are not that big a deal........

TMAllison · #5 12-26-2007, 11:14 AM

Start it up and with a bright flashlight look for air bubbles in the fuel line that exits the back of the pre-filter housing where the bottom of the pre-filter would be. Air in that line means the pre-filter oring or the line attaching to the prefilter is leaking. Air getting into the prefilter is about the only point that can cause a running engine to die.

The exception being a leak at the oring behind the shutoff valve.

Is also possible it is the SOV or the K40 realy causing the problem. That usually kills the engine suddenly; "as if key were turned off" so is pretty obvious.

The MAF fault should trip the CEL and is usually immediately noticable; no turbo boost, difficult to get engine over 3k rpm's and accellerates like a 240D.

dapperappy · #6 12-26-2007, 01:54 PM

hey guys, forgot to tell everyone merry christmas yesterday...my bad!
I have studied the records, actually looked at them before i bought the car and made a list of everthing they have done to the car and just in case anyone's interested or it will help i'll list here:
6-19-00 oil change 6,755 miles
3-1-01 service 'A' performed, rear door adjusted 13,785
10-25-02 check engine lt on- glow output control module replaced, faulty diesel engine control module replaced, defective battery replaced 30,988
8-5-03 transmission will not shift, won't start if cold, rough idle -replaced valve body and control unit, replaced shifter unit and 5 defective glow plugs, replaced defective volume air flow sensor, R&R intake manifold 35,942
11-20-03 service 'B' performed. Replaced all brake pads 41,232
6-16-04 driver's rear window fell and A/C not cold - evaporator leaking. Replace window regulator, evaporator, exp valve, drier and blower regulator 44,763
11-2-05 service 'A' performed 56,959
6-19-06 battery light came on briefly- replaced battery 62,942
7-20-06 Heavy fuel smell- replaced 5 fuel lines and shutoff valve 63,593
3-7-07 service 'B' performed-also replaced cracked main serpentine belt 68,257
11-23-07 rear pass. window not working- replaced regulator. Also replaced belt tensioner shock per EST. Also rear diff seal leak-replaced seals.73,139

Sorry so long but wanted to let you know. Also, i had just filled up on gas in town before heading home, was down to a quarter of a tank and got really cheap gas. Does it matter where you buy diesel or can you just go for the cheapest you can find?

vstech · #7 12-26-2007, 01:56 PM

you mean fuel or diesel, not gas right?

Hatterasguy · #8 12-26-2007, 02:01 PM

Replace both of the fuel filters, and don't forget to get an O ring for the pre filter. If the fuel filters don't fix it then check the clear fuel lines for air, but start with the simple things first.

Diesel fuel is dirty, on gas cars you almost never change the fuel filters. On diesels I do mine every year, but ever other is probably fine.

A bad MAF would trigger the CE light and kill the turbo. So it would run fine, it just wouldn't have any power.